Amazon NARF Listings
Amazon NARF program is a new program for FBA: North America Remote Fulfillment.
If your Amazon account is enrolled in Amazon NARF program, Teapplix will not be able to update the inventory quantity on the listings. You will see the following error from Amazon on the Teapplix Alert page:
An FBA offer already exists on this SKU. To create a seller fulfilled SKU, either create a new SKU or make the SwitchFulfillmentTo value MFN.
If you want to allow inventory update on Amazon listings, you would need to make sure your account is not enrolled in the NARF program.
You can go to the following page, it will offer you a link to un-enroll from the NARF program.